Agenda

Day 1

Network Programmability and Automation 101

What is Software Defined Networking?

Openflow

Network Functions Virtualization

Virtual switching

Network virtualization

Device APIs

Network Automation

Bare-metal switching

Data center network fabrics

SD-WAN

Controller networking

Network Automation

Why

• Simplified Architectures
• Deterministic Outcomes
• Business Agility

Types

• Device Provisioning
• Data Collection
• Migrations
• Configuration Management
• Compliance
• Reporting
• Troubleshooting

Application Programming Interfaces (APIs)

• SNMP
• SSH/Telnet and the CLI
• NETCONF
• RESTful APIs

Data Formats, Data Models and Config Templates

XML

<rpc-reply xmlns:junos="http://xml.juniper.net/junos/13.3R5/junos">
    <software-information>
        <host-name>M320-TEST-re0</host-name>
        <product-model>m320</product-model>
        <product-name>m320</product-name>
        <junos-version>13.3R5.9</junos-version>
    </software-information>
    <cli>
        <banner>{master}</banner>
    </cli>
</rpc-reply>

YAML

---
parameter_defaults: 
  ControlPlaneDefaultRoute: "192.0.2.1"
  ControlPlaneSubnetCidr: 24
  DnsServers:
    - "192.168.23.1"
  EC2MetadataIp: "192.0.2.1" 
  ExternalAllocationPools:
    - end: "10.0.0.250"
      start: "10.0.0.4"
  ExternalNetCidr: "10.0.0.1/24"
  NeutronExternalNetworkBridge: ""

JSON

{
  "parameter_defaults": {
    "ControlPlaneDefaultRoute": "192.0.2.1", 
    "ControlPlaneSubnetCidr": "24", 
    "DnsServers": [
        "192.168.23.1"
    ], 
    "EC2MetadataIp": "192.0.2.1", 
    "ExternalAllocationPools": [
        {
            "end": "10.0.0.250", 
            "start": "10.0.0.4"
        }
    ], 
    "ExternalNetCidr": "10.0.0.1/24", 
    "NeutronExternalNetworkBridge": ""
  }
}

YANG

 module configuration {
  namespace "http://xml.juniper.net/xnm/1.1/xnm";
  prefix junos;
  organization
    "Juniper Networks, Inc.";
  revision "2015-09-11" {
    description "Initial revision";
  }
  typedef ipv4addr {
    type string;
  }
  grouping juniper-config {
    container backup-router {
      description "IPv4 router to use while booting";
      leaf address {
        description "Address of router to use while booting";
        type ipv4addr;
        mandatory true;
      }
      presence "enable backup-router";
      leaf-list destination {
        description "Destination network reachable through the router";
        type ipv4prefix;
      }
    }
    ...

https://raw.githubusercontent.com/Juniper/yang/master/14.2/configuration.yang

JINJA

{% for key, value in vlanDict.iteritems() -%}
vlan {{ key }}
    name {{ value }}
{% endfor %}

>>> vlanDict = {123: 'TEST-VLAN-123', 234: 'TEST-VLAN-234', 345: 'TEST-VLAN-345'}
>>> from jinja2 import Environment
>>> env = Environment(loader=FileSystemLoader('./Templates/'))
>>> template = env.get_template('ourtemplate')
>>> print template.render(vlanDict)

vlan 123
    name TEST-VLAN-123
vlan 234
    name TEST-VLAN-234
vlan 345
    name TEST-VLAN-345

Ansible 101

Review of automation tools

• Ansible
• Chef
• Puppet
• Salt
• StackStorm

Understanding how Ansible works

• Automating servers
  • Distributed execution
  • Copy via SSH python code and runs in every device
• Automating network devices
  • Centralised execution
  • Runs python code locally and reach network devices by SNMP, SSH or APIs

Basic files and defaults

• Inventory file: Contains the devices (ip or fqdn) that will be automated (and associated variables)
  • /etc/ansible/hosts
  • ANSIBLE_INVENTORY
  • -i, --inventory-file
• Variable files:
  • Group variables
    • group_vars/{name of group}.yml or
    • group_vars/{name of group}/{variables}.yml
  • Host variables
    • host_vars/{name of group}.yml or
    • host_vars/{name of group}/{variables}.yml

Inventory file

[barcelona-dc]
switch01
switch02

[madrid-dc]
172.31.200.1
switch03

[barcelona-cpe]
vmx1

[madrid-cpe]
172.22.3.1

[barcelona:children]
barcelona-dc
barcelona-cpe

Assigning variables

[all:vars]
ntp_server=10.20.30.4

[barcelona:vars]
ntp_server=192.168.0.1

[madrid:vars]
ntp_server=10.0.0.1

or

[barcelona-dc]
switch01 ntp_server=192.168.0.3
switch02

Variables' file

File: group_vars/barcelona-dc.yml

---
snmp:
    contact: Ausias March
    location: Barcelona Data Center, Passeig Colon
    communities:
        - community: public
          type: ro
        - community: private
          type: rw

Executing an Ansible Playbook

It's the file that contain your automation instructions

---
    - name: PLAY 1 - Configure Interface Speed
      hosts: barcelona-dc
      connection: local
      gather_facts: no

      tasks:

        - name: TASK1 - Get interface information
          ios_command:
            commands:
                - show run | include interfaces
            provider:
                username: myusername
                password: mypassword
                host: "{{ inventory_hostname }}"

Exercise 1

Goal

Experiment with basic Ansible automation

All you need is here: https://github.com/chadell/ansible-cumulus-vyos

Scenario

TODO

• list of things
• list of things

Agenda

Day 2

Writing Ansible Playbooks

Core modules

• command: used to send exec-level commands
  • ios_command, vyos_command, junos_command, and so on
• config: used to send configuration commands
  • ios_config, vyos_config, junos_config, and so on
• facts: used to gather information from network devices
  • ios_facts, vyos_facts, junos_facts, and so on

Note: to find out the parameters of each module (plus some examples), you can use the ansible-doc utility: $ ansible-doc ios_config

Creating and using configuration templates

1. Creating variable files
2. Creating Jinja templates
3. Generating network configuration files

Creating variable files (1)

group_vars/barcelona-dc.yml

---
snmp:
    contact: Ausias March
    location: Barcelona Data Center, Passeig Colon
    communities:
        - community: public
          type: ro
        - community: privat
          type: rw

Creating variable files (2)

group_vars/madrid-dc.yml

---
snmp:
    contact: Francisco de Quevedo
    location: Madrid Data Center, Paseo de la Castellana
    communities:
        - community: publico
          type: ro
        - community: privado
          type: rw

Creating variable files (3)

group_vars/all.yml

---
base_provider:
    username: vagrant
    password: vagrant
    host: "{{ inventory_hostname}}"

Creating Jinja templates (1)

templates/snmp/ios.j2

snmp-server location {{ snmp.location }}
snmp-server contact {{ snmp.contact }}
{% for community in snmp.communities %}
snmp-server community {{ community.community }} {{ community.type | upper }}
{% endfor %}

Creating Jinja templates (2)

templates/snmp/junos.j2

set snmp location {{ snmp.location }}
set snmp contact {{ snmp.contact }}
{% for community in snmp.communities %}
{% if community.type | lower == "rw" %}
set snmp community {{ community.community }} authorization read-write
{% elif community.type | lower == "ro" %}
set snmp community {{ community.community }} authorization read-only
{% endif %}
{% endfor %}

Generating network configuration files

Ensuring a configuration exists

1. Idempotency
2. Using the config module
3. Understanding check mode, verbosity and limit

Gathering and viewing network data

1. Using the core facts modules
2. Using the debug module

Issuing show commands and writing data to a file

1. Using the register task attribute

Performing compliance checks

Generating reports

Using 3rd-party Ansible modules

NAPALM modules

Bring your own module

• Installing 3rd party modules

Exercise 2

Goal

Extend Ansible feautures to provision a network

All you need is here: https://github.com/chadell/ansible-cumulus-vyos

Scenario

TODO

• list of things
• list of things